Decorative member and manufacturing method thereof

ABSTRACT

A decorative member includes: a transparent resin layer provided on a rear surface thereof with a general portion, a stepped portion recessed or protrudingly provided with respect to the general portion, and an inclination portion provided between the stepped portion and the general portion; and a decorative layer provided on the rear surface, wherein: an inclination angle of the inclination portion with respect to a normal line of the general portion is equal to or more than 25° and is equal to or less than 40°; a width of the inclination portion is large beyond 0.38 mm and is equal to or less than 1 mm; and the decorative layer includes: a first layer that covers the stepped portion of the rear surface; and a second layer that covers a part of the rear surface, which is not covered by at least the first layer.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2015-224061, filed on Nov. 16, 2015, theentire contents of which are incorporated herein by reference.

BACKGROUND

1. Field of the Invention

The present invention relates to a decorative member used in an emblemand the like and a manufacturing method thereof.

2. Description of the Related Art

A radio wave transmission cover for a vehicle is generally provided witha decorative layer for displaying various designs. The decorative layeris a relative thin layer formed by metal deposition, film transfer andthe like. The radio wave transmission cover is mainly configured with atransparent resin layer of a front side and a base layer of a rear sidewhile interposing the decorative layer between the transparent resinlayer and the base layer. The radio wave transmission cover is formed tohave a uniform thickness such that transmission/reception of millimeterwaves is not affected.

In order to express three-dimensional characters or figures on the radiowave transmission cover, for example, a rear surface of the transparentresin layer is employed as an uneven surface having a general part and aconcave part recessed with respect to the general part, a blackenedprint layer is formed in the general part, and then an indium layer isformed on the entire of the uneven surface by a vacuum deposition methodas disclosed in JP-A-2009-17125.

In the manufacturing method of the radio wave transmission coverdisclosed in JP-A-2009-17125, however, the indium layer covers theentire of the uneven surface of the transparent resin layer. Indium hasa radio wave transmission characteristic, but when the entire surface ofthe transparent resin layer is covered with the indium, since theattenuation and the phase difference of radio waves of the radio wavetransmission cover become large, radio wave transmission performance isreduced.

In this regard, it is considered to partially print the indium layeronly in the concave part of the uneven surface of the transparent resinlayer. As an indium printing method, a screen printing method, a hotstamping method and the like are considered.

However, the screen printing method is a method in which ink is pushedout from a screen mesh and is printed. When the position of the screenmesh is slightly shifted, the boundary of a print part is shifted fromthe boundary part of a concave part and a convex part. Since theboundary line of characters and figures of the concave part or theconvex part is not clear, appearance becomes worse.

The hot stamping method is a method in which a transfer film having asheet printed with the indium layer is arranged on the uneven surface ofthe transparent resin layer, and the transfer sheet is pressed to theuneven surface by using a hot stamp while heating it, so that the indiumlayer is transferred to the uneven surface. In this method, there mayoccur a transfer error such as non-attachment of the indium layer on thesheet to the uneven surface.

Furthermore, accurately forming a metal layer of indium and the likeonly in the concave part of the uneven surface of the transparent resinlayer is an issue of the decorative member other than the radio wavetransmission cover.

SUMMARY

The present invention has been made to solve the above-describedproblem, and an object of the present invention is to provide adecorative member capable of accurately forming a design on an unevensurface of a transparent resin layer and a manufacturing method thereof.

According to an aspect of the present invention, there is provided amanufacturing method of a decorative member including: preparing atransparent resin layer provided on a rear surface thereof with ageneral portion, a stepped portion recessed or protrudingly providedwith respect to the general portion, and an inclination portion providedbetween the stepped portion and the general portion, an inclinationangle of the inclination portion with respect to a normal line of thegeneral portion being equal to or more than 25° and being equal to orless than 40° and a width of the inclination portion being large beyond0.38 mm and being equal to or less than 1 mm; disposing a first layer onat least the stepped portion and the inclination portion of the rearsurface of the transparent resin layer; allowing a part covering thestepped portion in the first layer to remain and separating an excesspart, other than the covering the stepped portion, in the first layer bylaser irradiation; and disposing a second layer on a part not coveredwith at least the first layer of the rear surface of the transparentresin layer.

According to another aspect of the present invention, there is provideda decorative member including: a transparent resin layer provided on arear surface thereof with a general portion, a stepped portion recessedor protrudingly provided with respect to the general portion, and aninclination portion provided between the stepped portion and the generalportion; and a decorative layer provided on the rear surface of thetransparent resin layer, wherein: an inclination angle of theinclination portion with respect to a normal line of the general portionis equal to or more than 25° and is equal to or less than 40°; a widthof the inclination portion is large beyond 0.38 mm and is equal to orless than 1 mm; and the decorative layer includes: a first layer thatcovers the stepped portion of the rear surface of the transparent resinlayer; and a second layer that covers a part of the rear surface of thetransparent resin layer, which is not covered by at least the firstlayer.

According to the manufacturing method of the decorative member of theinvention, the first layer is disposed on at least the concave or convexstepped portion and the inclination portion on the rear surface of thetransparent resin layer, and the part covering the stepped portion inthe first layer is allowed to remain, and the excess part in the firstlayer, other than the part covering the stepped portion, is separated bythe laser irradiation. Therefore, it is possible to accurately separatethe excess part. When the first layer is viewed from the surface of thetransparent resin layer, it is possible to view an accurate design.

The inclination angle of the inclination portion with respect to thenormal line of the general portion is 25° to 40° and the width of theinclination portion is large beyond 0.38 mm and is equal to or less than1 mm. The width of the inclination portion is larger than separationtolerance when the first layer is separated by the laser irradiation.Therefore, even though a molding dimensional error or a positional shiftat the time of installation of a laser irradiation jig occurs in thetransparent resin layer, these errors are absorbed, so that the boundaryline between the first layer and the separation part, from which theexcess part has been separated, can be positioned on the inclinationportion. The boundary line between the first layer and the separationpart is allowed to be positioned on the inclination portion, so that theboundary line is prevented from being shifted on the general portion orthe stepped portion.

Since the inclination angle of the inclination portion is 25° to 40°,when the first layer is viewed from the surface side of the transparentresin layer, the first layer remaining on the inclination portion isdifficult to be viewed. The first layer is viewed as if it covers onlythe stepped portion, so that it is possible to three-dimensionally viewthe first layer with a good appearance.

The separation of the excess part of the first layer is performed by thelaser irradiation. Since the laser has a high degree of accuracy of anirradiation position, it is possible to accurately separate the excesspart of the first layer. Therefore, according to the invention, ascompared with the case in which the first layer has been formed on thestepped portion by printing such as screen printing, it is possible toaccurately form a design of the first layer.

For example, in the case of forming the first layer on the steppedportion by screen printing, the printing may not be performed dependingon the rear surface shape of the transparent resin layer. That is, inthe screen printing, since ink is pushed out from a screen mesh and isprinted, the screen mesh need to be parallel to the rear surface of thetransparent resin layer. When there is a protruding part which largelyprotrudes on the rear surface, since the protruding part causes flowmark or weld to the transparent resin layer at the time of molding, nodesign is established.

In contrast, when the laser is used, it is possible to reliably separatethe excess part of the first layer regardless of the rear surface shapeof the transparent resin layer.

In the invention, the general portion and the stepped portion of therear surface of the transparent resin layer may be a concave portion ora convex portion. The first layer is formed on the stepped portion.

The decorative member of the invention is manufactured by theaforementioned decorative member manufacturing method, so that it ispossible to view a design accurately formed on the uneven surface of thetransparent resin layer.

Since the inclination angle and the width of the inclination portion arein the aforementioned range, it is possible to three-dimensionally viewthe first layer with a good appearance.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description given hereinbelow and the accompanying drawingwhich is given by way of illustration only, and thus is not limitativeof the present invention and wherein:

FIG. 1 is a front view of a front grill to which a decorative member ofa first embodiment of the invention has been attached:

FIG. 2 is a front view of the decorative member of the first embodiment:

FIG. 3 is a sectional view taken along line A-A of FIG. 2;

FIG. 4 is an enlarged view of a circled part of FIG. 3;

FIG. 5 is an explanation diagram of an inclination portion of a rearsurface of a transparent resin layer of the first embodiment;

FIG. 6 is a flowchart illustrating a manufacturing method of thedecorative member of the first embodiment;

FIG. 7 is a sectional view of the transparent resin layer, in which anouter peripheral part of the rear surface has been subjected to blackprinting, for explaining the manufacturing method of the decorativemember of the first embodiment;

FIG. 8 is a sectional view of the transparent resin layer on which afirst layer has been disposed, which is subsequent to FIG. 7;

FIG. 9 is a sectional view of the transparent resin layer after aseparation step, which is subsequent to FIG. 8:

FIG. 10 is a sectional view of the transparent resin layer on which asecond layer has been disposed, which is subsequent to FIG. 9:

FIG. 11 is a front view of a decorative member of a second embodiment;

FIG. 12 is a sectional view taken along line B-B of FIG. 11;

FIG. 13 is a flowchart illustrating a manufacturing method of thedecorative member of the second embodiment;

FIG. 14 is a sectional view of the transparent resin layer, on which apattern layer and a first layer have been disposed, for explaining themanufacturing method of the decorative member of the second embodiment:

FIG. 15 is a sectional view of the transparent resin layer after aseparation step, which is subsequent to FIG. 14;

FIG. 16 is a sectional view of the transparent resin layer on which asecond layer has been disposed, which is subsequent to FIG. 15;

FIG. 17 is a partially enlarged sectional view of a decorative member ofa third embodiment:

FIG. 18 is a sectional view of a transparent resin layer, in which ascreen mesh has been arranged at a rear surface side, for explaining amanufacturing method of the decorative member of the third embodiment;

FIG. 19 is a sectional view of a transparent resin layer on which afirst layer has been formed on a rear surface by a screen printingmethod, which is subsequent to FIG. 18; and

FIG. 20 is a sectional view of the transparent resin layer when aseparation step is being performed, which is subsequent to FIG. 19.

DETAILED DESCRIPTION OF THE INVENTION First Embodiment

A decorative member and a manufacturing method thereof according to afirst embodiment will be described with reference to each of drawings.

As illustrated in FIGS. 1 and 2, a decorative member 1 according to thepresent embodiment is a millimeter wave transmission cover attached tothe center of a front grill 9 of a vehicle. The decorative member 1 isprovided at a rear surface side thereof with a millimeter waveoscillation receiver (not illustrated).

As illustrated in FIG. 3, the decorative member 1 is a thin plate andthicknesses of its all parts are set to be n times of ½ of a wavelengthof a millimeter wave. In the decorative member 1, the center is gentlycurved to protrude to a surface 1 a side. The decorative member 1 has atransparent resin layer 2, a base layer 5, and a decorative layer 3interposed between the transparent resin layer 2 and the base layer 5.The transparent resin layer 2 is made of a transparent resin material,and for example, PC (polycarbonate) is used.

A surface 2 a of the transparent resin layer 2 is a smooth surface. Arear surface 2 b of the transparent resin layer 2 has an outerperipheral part 21 and an inner part 22 positioned at an inner side fromthe outer peripheral part 21 and recessed with respect to the outerperipheral part 21. A depth T of the inner part 22 from the outerperipheral part 21 is 2.5 mm.

The outer peripheral part 21 has a flat shape. The outer peripheral part21 is covered by a black translucent outer peripheral print part 35.

As illustrated in FIGS. 4 and 5, the inner part 22 has a general portion23, a stepped portion 25 recessed with respect to the general portion23, and an inclination portion 26 provided between the general portion23 and the stepped portion 25. A height difference H between the steppedportion 25 and the general portion 23 of the rear surface 2 b of thetransparent resin layer 2, that is, a height of the inclination portion26 is equal to or more than 0.3 mm and is equal to or less than 1.0 mm.In the present embodiment, the height difference H between the steppedportion 25 and the general portion 23 of the rear surface 2 b of thetransparent resin layer 2 is 0.5 mm.

As illustrated in FIG. 5, the inclination portion 26 is interposedbetween the general portion 23 and the stepped portion 25. Aninclination angle α of the inclination portion 26 with respect to anormal line D of the general portion 23 is 30°. An upper end 26 a of theinclination portion 26 is a part connected to the general portion 23,and a lower end 26 b of the inclination portion 26 is a part connectedto the recessed stepped portion 25. R1 and R2 of the upper end 26 a andthe lower end 26 b of the inclination portion 26 are all chamfered in anarc shape having a curvature radius of 0.3 mm. A width W from the upperend 26 a to the lower end 26 b of the inclination portion 26 when theinclination portion 26 has been projected along the normal line of therear surface 2 b of the transparent resin layer 2 is 0.6 mm.

As illustrated in FIG. 4, the decorative layer 3 is provided to the rearsurface 2 b side of the transparent resin layer 2, and has a first layer31 and a second layer 32 sequentially arranged from the rear surface 2 bside. The first layer 31 includes a metal layer having a radio wavetransmission characteristic. As the metal layer, an indium layer ispreferable. The indium layer may have a sea-island structure in whichindium exists insularly in various places from the standpoint of a radiowave transmission characteristic. The second layer 32 is a black coatinglayer. The first layer 31 has a thickness of about 40 nm to 50 nm andthe second layer 32 has a thickness of about 30 μm to 40 μm.

The first layer 31 covers the recessed stepped portion 25 of the rearsurface 2 b of the transparent resin layer 2. The second layer 32 coversthe entire of the rear surface 2 b of the transparent resin layer 2. Thefirst layer 31 including the indium is positioned at the recessedstepped portion 25 and is positioned near the surface 1 a of thedecorative member 1 as compared with the second layer 32 including theblack coating layer. As illustrated in FIG. 2, when the decorativemember 1 is viewed from the surface 1 a side, a black character of theblack coating layer is viewed in the brightly colored area of theindium. The brightly colored figure floats up to a front side from theblack area and is three-dimensionally viewed.

The base layer 5 is made of a colored resin material, for example, AES(acrylonitrile ethylene styrene copolymer).

A manufacturing method of the decorative member 1 of the presentembodiment will be described using a flowchart of FIG. 6.

In step S10 (preparation step), polycarbonate resin is injection-moldedusing a mold, so that the transparent resin layer 2 is obtained.

In step S20 (surface hard coat step), a hard coat process is performedfor the surface 2 a of the transparent resin layer 2.

In step S30 (rear surface printing step), as illustrated in FIG. 7,blank ink is printed on the outer peripheral part 21 of the rear surface2 b of the transparent resin layer 2 by a screen printing method and thelike, so that the black translucent outer peripheral print part 35 isformed on the outer peripheral part 21.

In step S40 (first layer disposing step), as illustrated in FIG. 8, thefirst layer 31 including indium is formed on the entire of the innerpart 22 of the rear surface 2 b of the transparent resin layer 2 by asputtering method. The first layer 31 may be formed by a depositionmethod.

In step S50 (separation step), as illustrated in FIG. 9, the transparentresin layer 2 is fixed to a jig such that the rear surface 2 b of thetransparent resin layer 2 is upward. In the first layer 31 on the rearsurface 2 b of the transparent resin layer 2, laser is irradiated to anexcess part B, other than a part A covering the stepped portion 25, sothat the excess part B is separated. As the laser irradiation device,MDV9920 (product name) manufactured by keyence Corporation has beenused. The laser irradiation energy per unit area is 0.45 mJ. In thelaser irradiation conditions, a laser spot diameter is 0.08 mm, a laserspot pitch is 0.064 mm, a laser frequency is 120 kHz, and a laserwavelength is 1064 nm. It is sufficient if laser transmittance is 5% to90%, and it is preferable that a laser movement speed is 600 mm/sec to1300 mm/sec. In this case, there is no discoloration due to laserburning of the transparent resin layer 2 and residue of the indium,which is the first layer 31, is also not seen.

The boundary between the irradiation area and the non-irradiation areaof the laser is set as a center 26 c in the width direction of theinclination portion 26. The excess part B separated by the laser is anarea from the general portion 23 and the upper end 26 a of theinclination portion 26 to the center 26 c in terms of design. Whenmeasuring a molding error range of the transparent resin layer 2, apositional shift range of a fixing jig for laser irradiation, and avariation range of a laser irradiation position, they are sequentially±0.17 mm, ±0.1 mm, and ±0.02 mm. Their total error is ±0.29 mm, and isseparation tolerance by which a separation position may be shifted withrespect to the transparent resin layer 2. On the other hand, asillustrated in FIGS. 4 and 9, the width W of the inclination portion 26is 0.6 mm and the inclination portion 26 exists in an area of ±0.3 mmfrom the center 26 c of the inclination portion 26. Since the shiftrange of the laser irradiation position with respect to the transparentresin layer 2 is ±0.29 mm, the laser enters into the width (±0.3 mm)from the center 26 c of the inclination portion 26. Therefore, when theexcess part B of the first layer 31 is separated by the laserirradiation, a boundary line L between the first layer 31 and theseparation part is positioned on the inclination portion 26. The firstlayer 31 does not almost remain in the upper end 26 a side of theinclination portion 26 and mainly remains in the lower end 26 b ascompared with the upper end 26 a side. The boundary line L between thefirst layer 31 and the separation part is positioned in the center 26 cof the inclination portion 26 in many cases.

In step S60 (second layer disposing step), as illustrated in FIG. 10,the second layer 32 is formed on the inner part 22 of the rear surface 2b side of the transparent resin layer 2 by coating using a black paint.The second layer 32 is an opaque black layer.

The black paint has been obtained by mixing coloring with a resinmaterial. For example, the coloring is carbon black and the resinmaterial is acryl resin; however, the invention is not limited thereto.

In step S70 (base layer formation step), the transparent resin layer 2is inserted into the mold and colored AES is injection-molded at therear surface 2 b side of the transparent resin layer 2, so that the baselayer 5 is formed on the entire of the rear surface 2 b side.

As above, the decorative member 1 of the present embodiment is obtained.

According to the manufacturing method of the decorative member 1 of thepresent embodiment, the first layer 31 is disposed on the entire of therear surface 2 b of the transparent resin layer 2, the part A coveringthe stepped portion 25 in the first layer 31 is allowed to remain, andthe excess part B, other than the part A, is separated by laserirradiation. Therefore, it is possible to accurately separate the excesspart B. When the first layer 31 is viewed from the surface 2 a of thetransparent resin layer 2, it is possible to view an accurate design.

The inclination angle α of the inclination portion 26 with respect tothe normal line D of the general portion 23 is 25° to 40° and the widthW of the inclination portion 26 is large beyond 0.38 mm and is equal toor less than 1 mm. In the present embodiment, the inclination angle α ofthe inclination portion 26 with respect to the normal line D of thegeneral portion 23 is 30°, and the width W of the inclination portion 26is 0.6 mm.

The width W of the inclination portion 26 is larger than the range 0.58mm of the separation tolerance (±0.29 mm). When laser is irradiatedaiming at the center 26 c of the inclination portion 26, even though alaser irradiation positional shift occurs at the upper end 26 a side orthe lower end 26 b side from the center 26 c, the inclination portion 26absorbs the shift, so that it is possible to allow the boundary line Lbetween the first layer 31 and the separation part, from which theexcess part B has been separated, to be positioned on the inclinationportion 26. Since the shift of the boundary line L between the firstlayer 31 and the separation part is positioned on the inclinationportion 26, the boundary line L is prevented from being shifted on thegeneral portion 23 or the stepped portion 25. When the first layer 31 isviewed from the surface 2 a of the transparent resin layer 2, since thefirst layer 31 is viewed as if it covers only the stepped portion 25, itis possible to three-dimensionally view the first layer 31 with a goodappearance.

When the inclination angle α is smaller than 25°, even though a moldingdimensional error of the transparent resin layer 2 or a laserirradiation positional shift at the time of installation of a laserirradiation jig occurs, the inclination portion 26 may not absorb theshift, or the boundary line L between the first layer 31 and theseparation part may be positioned on the general portion 23 or thestepped portion 25. When the inclination angle α exceeds 40°, if it isviewed from the surface 1 a side of the decorative member 1, theinclination portion 26 is viewed. The boundary line L on the inclinationportion 26 is apparently viewed and the contour of the first layer 31appears to protrude as compared with the contour of the stepped portion25, so that the appearance of the first layer 31 may be reduced.

In the separation step, the separation of the excess part B of the firstlayer 31 is performed by the laser irradiation. Since the laser has ahigh degree of accuracy of an irradiation position, it is possible toaccurately separate the excess part B of the first layer 31. Therefore,according to the separation step of the present embodiment, as comparedwith the case in which the first layer 31 has been formed on the steppedportion 25 by printing such as screen printing, it is possible toaccurately form a design of the first layer 31.

For example, when the first layer 31 is formed on the stepped portion 25by screen printing, the printing may not be performed depending on therear surface shape of the transparent resin layer 2. That is, in thescreen printing, since ink is pushed out from a screen mesh and isprinted, the screen mesh need to be parallel to the rear surface 2 b ofthe transparent resin layer 2. When there is a protruding part whichlargely protrudes on the rear surface 2 b, since the protruding partcauses flow mark or weld to the transparent resin layer 2 at the time ofmolding, no design is established.

In contrast, when the laser is used, it is possible to reliably separatethe excess part B of the first layer 31 regardless of the rear surfaceshape of the transparent resin layer 2, so that the first layer 31 canremain on the stepped portion 25.

The decorative member 1 of the present embodiment is manufactured by theaforementioned decorative member manufacturing method, so that it ispossible to view a design accurately formed on the uneven surface of thetransparent resin layer 2.

When the rear surface 2 b of the transparent resin layer 2 after laserirradiation is observed by SEM (scanning electronic microscope), asea-island structure is recognized in which indium exists insularly inmany places of the part A of the first layer 31 subjected to no laserirradiation. The first layer 31 has not been observed in the separationpart. In the inclination portion 26, the boundary line L between thepart A of the first layer 31 and the separation part is arranged. Whenthe decorative member 1 is viewed from the surface 1 a side, since thefirst layer 31 is viewed as if it covers only the stepped portion 25, itis possible to three-dimensionally view the first layer 31 with a goodappearance. Around the boundary line L of the part A, the sea-islandstructure of the indium remains. Around the boundary line L of the partA, residues of PC (components of the transparent resin layer) having asize of about 1 μm have been observed. Since the thickness of the secondlayer 32 is 30 μm, the residues of about 1 μm do not affect externalappearance, an adhesion property, and millimeter wave attenuation.

In the transparent resin layer, when measuring optical attenuation ofthe separation part, from which the first layer has been separated bylaser irradiation, and optical attenuation of the transparent resinlayer before the first layer is formed, both are low with the samedegree.

The color of the transparent resin layer (a resin layer before beingprocessed) before the first layer is formed and the color of thetransparent resin layer (a resin layer after separation) after laserseparation have been measured with an L*a*b* display system. The laserirradiation conditions are similar to the aforementioned conditions ofthe present embodiment. From the measured values of the color of theresin layer before being processed and the color of the resin layerafter separation, a color difference ΔE of the resin layer afterseparation from the resin layer before being processed has beenobtained. When the color difference ΔE is smaller than 1.5, it can beunderstood that it is not possible to recognize the color difference ofthe two. These results are illustrated in Table 1 below.

TABLE 1 Transmission color tone L*a*b* value L* a* b* Color differenceΔE Resin layer before being 95.79 −0.08 0.31 processed Resin layer afterseparation 95.33 −0.09 0.77 0.65

The color difference ΔE from the resin layer before being processed andthe resin layer after separation is 0.65. From this fact, it can beunderstood that laser is irradiated to the first layer, so that it ispossible to separate the first layer from the rear surface of thetransparent resin layer to the extent that the first layer is notrecognizable.

Second Embodiment

A decorative member 1 of the present embodiment is different from thefirst embodiment in that a pattern layer 36 is coated on the outerperipheral part 21 of the rear surface 2 b of the transparent resinlayer 2 as illustrated in FIGS. 11 and 12.

In order to manufacture the decorative member 1 of the presentembodiment, steps S10, S20, S30, and S40 have been performed asillustrated in FIG. 13, similarly to the first embodiment. On the rearsurface 2 b of the transparent resin layer 2 after step S40, the firstlayer 31 is formed on the entire of the inner part 22 (see FIG. 8).

After step S40 (first layer disposing step), step S45 (a partial coatingstep) is performed. In step S45, the pattern layer 36 is coated on apart of the outer peripheral part 21 of the rear surface 2 b of thetransparent resin layer 2 or the entire of the inner part 22 asillustrated in FIG. 14. In order to form the pattern layer 36, in thestate in which a part of the outer peripheral part 21, other than apattern layer formation part, is covered with a mask 8, the rear surface2 b of the transparent resin layer 2 is coated, and then the mask 8 isremoved. For the pattern layer 36, an opaque colored paint of a brownand the like has been used.

In step S50 (separation step), as illustrated in FIG. 15, in the firstlayer 31 and the pattern layer 36 on the rear surface 2 b of thetransparent resin layer 2, laser is irradiated to an excess part B,other than the part A covering the stepped portion 25, so that theexcess part B is separated. The laser irradiation conditions are similarto those of the first embodiment except that the irradiation energy perunit area is 3.2 mJ. The width W of the inclination portion 26 of therear surface 2 b of the transparent resin layer 2 is 0.6 mm and theinclination angle α of the inclination portion 26 is 30°. The width Wand the inclination angle α are similar to those of the firstembodiment. Since the width W is larger than separation tolerance (±0.29mm) due to the difference of laser irradiation as described in the firstembodiment, even though positional shift of laser irradiation occurs,the boundary line L between the first layer 31 and the pattern layer 36remaining after the separation and the separation part thereof ispositioned on the inclination portion 26.

In step S60 (second layer disposing step), as illustrated in FIG. 16, ablack coating layer is disposed at the rear surface 2 b side of thetransparent resin layer 2 as the second layer 32.

In step S70 (base layer formation step), as illustrated in FIG. 12, therear surface 2 b of the transparent resin layer 2, on which the secondlayer 32 has been formed, is covered with the base layer 5. Theformation of the base layer 5 has been performed similarly to the firstembodiment.

As above, the decorative member 1 of the present embodiment has beenobtained.

When the obtained decorative member 1 is viewed from the surface, thepattern layer 36 is recognized at the outer peripheral part 21 through atransparent black outer peripheral print part 35. At the inner part 22,the pattern layer 36 is conceal to the rear surface side of the firstlayer 31 and is not seen. At the inner part 22, the bright color of theindium of the first layer 31 stands out on a front side and isthree-dimensionally recognized in the black area of the second layer 32similarly to the first embodiment.

Third Embodiment

A decorative member 1 of the present embodiment is different from thefirst embodiment in that a first layer 310 of the decorative layer 3 isa black coating layer and a second layer 320 is an indium layer asillustrated in FIG. 17.

The first layer 310 is formed on a stepped portion 250 protrudinglyprovided in the inner part 22 of the rear surface 2 b of the transparentresin layer 2. On the rear surface 2 b of the transparent resin layer 2,the second layer 320, which is the indium layer, is formed on the entireof the inner part 22, including the first layer 310.

In order to manufacture the decorative member 1 of the presentembodiment, steps S10, S20, and S30 have been performed (see FIG. 6),similarly to the first embodiment. On the rear surface 2 b of thetransparent resin layer 2 after step S30, a black translucent outerperipheral print part 35 is formed on the outer peripheral part 21 (seeFIG. 7).

In step S40 (first layer disposing step), as illustrated in FIG. 18, ascreen mesh 7 is arranged at the rear surface 2 b side of thetransparent resin layer 2. In the screen mesh 7, holes 70 are opened inparts corresponding to the stepped portion 250 and an inclinationportion 260. As illustrated in FIGS. 18 and 19, black ink is pushed outfrom the holes 70 of the screen mesh 7, so that the first layer 310 isformed on the stepped portion 250 and the inclination portion 260. Inthe screen printing using the screen mesh 7, since printing positionaccuracy is lower than that of laser, the first layer 310 is formed onthe inclination portion 260 as well as the stepped portion 250 by thescreen printing, and the first layer 310 on the inclination portion 260is separated by laser in a subsequent separation step. The black inkused in the screen printing is similar to the black ink in step S60(second layer disposing step) in the first embodiment.

In step S50 (separation step), as illustrated in FIG. 20, laser isirradiated to an excess part B of the first layer 310, so that theexcess part B is separated. In this way, the first layer 310 remains onthe stepped portion 250 of the rear surface 2 b of the transparent resinlayer 2.

In the present embodiment, laser is set to be irradiated to an area froma general portion 230 to a center 260 c of the inclination portion 260.The excess part B separated by the laser is an area from a lower end 260b to the center 260 c of the inclination portion 260 in the first layer310 in terms of design. Similarly to the first embodiment, separationtolerance is +0.29 mm. The separation tolerance is smaller than thewidth W (±0.30 mm) from the center 260 c of the inclination portion 260.Therefore, also in the present embodiment, when the excess part B of thefirst layer 310 is separated by laser irradiation, the boundary line Lbetween the first layer 310 and the separation part is positioned on theinclination portion 260.

In step S60 (second layer disposing step), as illustrated in FIG. 17,the indium layer as the second layer 320 is disposed on the entire ofthe inner part 22. The indium layer can be disposed by a sputteringmethod or a deposition method.

Thereafter, step S70 (base layer formation step) is performed similarlyto the first embodiment, so that the decorative member 1 of the presentembodiment is obtained.

When the decorative member 1 of the present embodiment is viewed fromthe surface 1 a side, the bright color part of the second layer 320formed on the general portion 230 and including indium floats up and isthree-dimensionally and clearly seen during black coating.

In step S40 (first layer disposing step), the first layer 310 is formedas a coating layer by using the screen mesh 7. When positional shiftoccurs in the screen mesh 7, the first layer 310 causes positionalshift. However, since the first layer 310 is accurately trimmed by laserin step S50 (separation step), it is possible to form the first layer310 at an accurate position.

The first layer 310 is formed in advance on the stepped portion 250 andthe inclination portion 260 around the stepped portion 250 by the screenprinting, and a part of the first layer 310 covering the stepped portion250 is separated by laser afterward. Therefore, an area of a laserseparation area becomes small. It is possible to shorten a laserseparation time.

The decorative member 1 of the aforementioned embodiment is a radio wavetransmission cover for millimeter waves, but can also be used in a radiowave transmission cover for other electric waves. The decorative member1 of the aforementioned embodiment can also be used as emblems fordecoration. These emblems are not limited to vehicles, and can be usedin all scenes.

(1) The manufacturing method of the decorative member 1 of the presentembodiment includes a preparation step of preparing the transparentresin layer 2 provided on the rear surface 2 b thereof with the generalportions 23 and 230, the stepped portion 25 recessed or the steppedportion 250 protrudingly provided with respect to the general portions23 and 230, and the inclination portions 26 and 260 provided between thestepped portions 25 and 250 and the general portions 23 and 230,inclination angles α of the inclination portions 26 and 260 with respectto the normal lines D of the general portions 23 and 230 being 25° to40° and widths W of the inclination portions 26 and 260 being largebeyond 0.38 mm and being equal to or less than 1 mm, a first layerdisposing step of disposing first layers 31 and 310 on at least thestepped portions 25 and 250 and the inclination portions 26 and 260 ofthe rear surface 2 b of the transparent resin layer 2, a separation stepof allowing parts A covering the stepped portions 25 and 250 in thefirst layers 31 and 310 to remain and separating excess parts B, otherthan the parts A, in the first layers 31 and 310 by laser irradiation,and a second layer disposing step of covering parts not covered with atleast the first layers 31 and 310 of the rear surface 2 b of thetransparent resin layer 2.

According to the aforementioned configuration, the first layers 31 and310 are disposed on at least the concave or convex stepped portions 25and 250 and the inclination portions 26 and 260 in the rear surface 2 bof the transparent resin layer 2, and the parts A covering the steppedportions 25 and 250 in the first layers 31 and 310 are allowed toremain, and the excess parts B, other than the parts A, are separated bythe laser irradiation. Therefore, it is possible to accurately separatethe excess parts B. When the first layers 31 and 310 are viewed from thesurface 2 a of the transparent resin layer 2, it is possible to view anaccurate design.

The inclination angles α of the inclination portions 26 and 260 withrespect to the normal lines D of the general portions 23 and 230 are 25°to 40° and the widths W of the inclination portions 26 and 260 are largebeyond 0.38 mm and are equal to or less than 1 mm. The widths W of theinclination portions 26 and 260 are larger than separation tolerancewhen the first layers 31 and 310 are separated by the laser irradiation.Therefore, even though a molding dimensional error or a positional shiftat the time of installation of a laser irradiation jig occurs in thetransparent resin layer 2, these errors are absorbed, so that theboundary lines L between the first layers 31 and 310 and the separationparts, from which the excess parts B have been separated, can bepositioned on the inclination portions 26 and 260. The boundary lines Lbetween the first layers 31 and 310 and the separation parts are allowedto be positioned on the inclination portions 26 and 260, so that theboundary lines L are prevented from being shifted on the generalportions 23 and 230 or the stepped portions 25 and 250.

Since the inclination angles α of the inclination portions 26 and 260are 25° to 40°, when the first layers 31 and 310 are viewed from thesurface side of the transparent resin layer, the first layers 31 and 310remaining on the inclination portions 26 and 260 are difficult to beviewed. The first layer 31 is viewed as if it covers only the steppedportion 25, so that it is possible to three-dimensionally view the firstlayer 31 with a good appearance.

In the separation step, the separation of the excess parts B of thefirst layers 31 and 310 is performed by the laser irradiation. Since thelaser has a high degree of accuracy of an irradiation position, it ispossible to accurately separate the excess parts B of the first layers31 and 310. Therefore, according to the separation step of theaforementioned embodiment, as compared with the case in which the firstlayers 31 and 310 are formed on the stepped portions 25 and 250 byprinting such as screen printing, it is possible to accurately formdesigns of the first layers 31 and 310.

For example, in the case of forming the first layers 31 and 310 by thescreen printing, the printing may not be performed depending on the rearsurface shape of the transparent resin layer 2. That is, in the screenprinting, since ink is pushed out from a screen mesh and is printed, thescreen mesh need to be parallel to the rear surface 2 b of thetransparent resin layer 2. When there is a protruding part which largelyprotrudes on the rear surface 2 b, since the protruding part causes flowmark or weld to the transparent resin layer 2 at the time of molding, nodesign is established.

In contrast, when the laser is used, it is possible to reliably separatethe excess parts B of the first layers 31 and 310 regardless of theshape of the rear surface 2 b of the transparent resin layer 2, so thatit is possible to form designs of the first layers 31 and 310.

In the aforementioned embodiment, the general portions 23 and 230 andthe stepped portions 25 and 250 of the rear surface 2 b of thetransparent resin layer 2 may be concave portions or convex portions. Inthe separation step, the first layers 31 and 310 remain on the steppedportions 25 and 250.

(2) Preferably, the first layer is made of indium, and in the separationstep, irradiation energy per unit area of laser irradiated to the firstlayer is 0.3 mJ to 0.6 mJ. In this case, it is possible to sufficientlyseparate the excess part B of the first layer 31 by laser irradiationwithout a change in the color of the transparent resin layer 2.

(3) After the first layer disposing step, it is preferable to perform acoating step of forming a paint layer (the pattern layer 36) including apaint on the rear surface 2 b of the transparent resin layer 2 andincluding a part in which the first layer 31 has been formed. It ispossible to form a design with a good appearance.

(4) In the aforementioned (3), preferably, the first layer 31 is made ofindium and in the separation step, irradiation energy per unit area oflaser irradiated to an overlap part of the first layer 31 and the paintlayer (the pattern layer 36) is 2.5 mJ to 3.8 mJ. In this case, it ispossible to sufficiently separate the excess parts B of the first layer31 and the paint layer by laser irradiation without a change in thecolor of the transparent resin layer 2.

(5) In the separation step, preferably, the boundary between anirradiation area and a non-irradiation area of the laser is set as thecenters 26 c and 260 c in the width direction of the inclinationportions 26 and 260. Even though a molding dimensional error or apositional shift at the time of installation of a laser irradiation jigoccurs in the transparent resin layer 2, the inclination portions 26 and260 absorb these errors, so that the boundary lines L between the firstlayers 31 and 310 and the separation parts, from which the excess partsB have been separated, can be positioned on the inclination portions 26and 260.

(6) The decorative member 1 of the aforementioned embodiment is thedecorative member 1 having the transparent resin layer 2 provided on therear surface 2 b thereof with the general portions 23 and 230, thestepped portions 25 and 250 recessed or protrudingly provided withrespect to the general portions 23 and 230, and the inclination portions26 and 260 provided between the stepped portions 25 and 250 and thegeneral portions 23 and 230, and the decorative layer 3 provided on therear surface 2 b of the transparent resin layer 2, the inclinationportions 26 and 260 are provided between the stepped portions 25 and 250and the general portions 23 and 230, the inclination angles α of theinclination portions 26 and 260 with respect to the normal lines D ofthe general portions 23 and 230 being 25° to 40°, the widths W of theinclination portions 26 and 260 are large beyond 0.38 mm and are equalto or less than 1 mm, and the decorative layer 3 has the first layers 31and 310 that cover the stepped portions 25 and 250 of the rear surface 2b of the transparent resin layer 2, and the second layers 32 and 320that cover parts of the rear surface 2 b of the transparent resin layer2, which are not covered by at least the first layers 31 and 310.

The decorative member 1 of the present embodiment is manufactured by theaforementioned manufacturing method of the decorative member 1, so thatit is possible to view a design accurately formed on the uneven surfaceof the transparent resin layer 2.

Since the inclination angle α and the width W of the inclination portion26 are in the aforementioned range, it is possible tothree-dimensionally view the first layers 31 and 310 with a goodappearance.

(7) Preferably, in the stepped portions 25 and 250 of the rear surface 2b of the transparent resin layer 2, a height difference H with thegeneral portions 23 and 230 is equal to or more than 0.3 mm and is equalto or less than 1.0 mm. By the height difference between the firstlayers 31 and 310 formed on the recessed or protrudingly providedstepped portions 25 and 250 and the second layers 32 and 320 formed onthe general portions 23 and 230, it is possible to view athree-dimensional design.

(8) Preferably, any one of the first layers 31 and 310 and the secondlayers 32 and 320 is a metal layer and the other one of the first layers31 and 310 and the second layers 32 and 320 is a colored layer. Bycontrast between a bright design due to the metal layer and a design dueto the colored layer, it is possible to realize a design having anappearance.

(9) Preferably, the metal layer is made of indium. Since the indium hasa radio wave transmission characteristic, the decorative member 1 of thepresent embodiment can be used as a radio wave transmission cover.

(10) Preferably, the boundary line L between parts covered with thefirst layers 31 and 310 on the rear surface 2 b of the transparent resinlayer 2 and parts not covered with the first layers 31 and 310 ispositioned on the inclination portions 26 and 260. In this case, eventhough disposal positions of the first layers 31 and 310 are shiftedduring a manufacturing process, it is possible to allow the first layerto reliably cover the entire of the stepped portions 25 and 250. Sincethe inclination portions 26 and 260 have the aforementionedpredetermined inclination angle α, when it is viewed from the surface 1a side of the decorative member 1, the first layers 31 and 310 on theinclination portions 26 and 260 are not almost seen and it seems as ifthe first layers 31 and 310 are disposed only on the stepped portions 25and 250. By the height difference H between the first layers 31 and 310and the second layers 32 and 320, it is possible to view athree-dimensional design.

In addition, it is sufficient if a decorative member has the followingaspects.

(11) Preferably, the rear surface 2 b of the transparent resin layer 2has a base area (the outer peripheral part 21) and a main area (theinner part 22) recessed or protrudingly provided with respect to thebase area, the main area has the general portions 23 and 230, thestepped portions 25 and 250, and the inclination portions 26 and 260,and a height difference between the main area and the base area is equalto or more than 2.5 mm. In the main area, a design is formed by thedecorative layer 3 covering the stepped portions 25 and 250. When themain area has been protrudingly provided with respect to the base area,the design formed in the main area is seen to float up. When the mainarea has been recessed with respect to the base area, the design formedin the main area is seen to be deeply sunk with respect to the basearea. As described above, since the height difference of the main areawith respect to the base area is equal to or more than 2.5 mm, it ispossible to more three-dimensionally view the design formed in the mainarea. Even if there is a large height difference equal to or more than2.5 mm, it is possible to accurately and reliably perform the separationstep by laser irradiation.

(12) Preferably, the decorative layer 3 is covered by the base layer 5.The decorative layer is disposed between the transparent resin layer 2and the base layer 5, so that the decorative member is easily used as anemblem or a radio wave transmission cover.

(13) Preferably, the decorative member is a radio wave transmissioncover.

What is claimed is:
 1. A decorative member comprising: a transparentresin layer provided on a rear surface thereof with a general portion, astepped portion recessed or protrudingly provided with respect to thegeneral portion, and an inclination portion provided between the steppedportion and the general portion, and a decorative layer provided on therear surface of the transparent resin layer, wherein: an inclinationangle of the inclination portion with respect to a normal line of thegeneral portion is equal to or more than 25° and is equal to or lessthan 40°; a width of the inclination portion is large beyond 0.38 mm andis equal to or less than 1 mm; and the decorative layer includes: afirst layer that covers the stepped portion of the rear surface of thetransparent resin layer; and a second layer that covers a part of therear surface of the transparent resin layer, which is not covered by atleast the first layer.
 2. The decorative member according to claim 1,wherein in the stepped portion of the rear surface of the transparentresin layer, a height difference with the general portion is equal to ormore than 0.3 mm and is equal to or less than 1.0 mm.
 3. The decorativemember according to claim 1, wherein any one of the first layer and thesecond layer is a metal layer, and the other one of the first layer andthe second layer is a colored layer.
 4. The decorative member accordingto claim 3, wherein the metal layer is made of indium.
 5. The decorativemember according to claim 1, wherein a boundary line between a partcovered with the first layer on the rear surface of the transparentresin layer and a part not covered with the first layer is positioned onthe inclination portion.
 6. A manufacturing method of a decorativemember comprising: preparing a transparent resin layer provided on arear surface thereof with a general portion, a stepped portion recessedor protrudingly provided with respect to the general portion, and aninclination portion provided between the stepped portion and the generalportion, an inclination angle of the inclination portion with respect toa normal line of the general portion being equal to or more than 25° andbeing equal to or less than 40° and a width of the inclination portionbeing large beyond 0.38 mm and being equal to or less than 1 mm;disposing a first layer on at least the stepped portion and theinclination portion of the rear surface of the transparent resin layer;allowing a part covering the stepped portion in the first layer toremain and separating an excess part, other than the covering thestepped portion, in the first layer by laser irradiation; and disposinga second layer on a part not covered with at least the first layer ofthe rear surface of the transparent resin layer.
 7. The manufacturingmethod of the decorative member according to claim 6, wherein the firstlayer is made of indium, and when the excess part is separated,irradiation energy per unit area of laser irradiated to the first layeris equal to or more than 0.3 mJ and is equal to or less than 0.6 mJ. 8.The manufacturing method of the decorative member according to claim 6,further comprising: forming a paint layer made of a paint on the rearsurface of the transparent resin layer and including a part in which thefirst layer has been formed, after the first layer is disposed.
 9. Themanufacturing method of the decorative member according to claim 8,wherein the first layer is made of indium, and when the excess part isseparated, irradiation energy per unit area of laser irradiated to anoverlap part of the first layer and the paint layer is equal to or morethan 2.5 mJ and is equal to or less than 3.8 mJ.
 10. The manufacturingmethod of the decorative member according to claim 6, wherein when theexcess part is separated, a boundary between an irradiation area and anon-irradiation area of the laser is set as a center in a widthdirection of the inclination portion.